It is frequently desirable to disconnect a final drive for a track-type vehicle when the vehicle is being towed. Although the transmission for the vehicle is normally placed in neutral during towing, hydrostatic motors sometimes employed in the vehicle's final drive remain operatively connected to the drive sprockets or the tracks. Thus, the motors are driven by the sprockets during towing which may result in damage to the motors due to lubricant starvation and frictional drag occasioned between the rotating components thereof.
In addition, a normally engaged and hydraulically released brake is usually integrated into the final drive. Since the vehicle's power plant may be nonoperative during the towing, the brake can not be released hydraulically unless special release mechanisms are employed therefor.
The present invention is directed to overcoming one or more of the problems as set forth above.
According to the present invention, there is provided a drive disconnect device for a power train contained within the housing and having first and second rotary members said first member being movable between a first position at which said first and second members are engaged to transmit power therebetween and a second position at which the first member is disconnected from the second member. The housing has a threaded bore in axial alignment with the first member. The drive disconnect drive comprises a cylindrical cage having an outer surface, an external thread and first and second grooves formed in the outer surface, said first groove being axially spaced from the second groove and said external thread being threadably positionable within the threaded bore. The cage is rotatably connected to the first member and is of a construction sufficient for moving the first member from the second position to the first position in response to the cage being rotated in a first direction and for moving the first member from the first position to the second position in response to the cage being rotated in an opposite direction. A lock member is detachably connectable to the housing and is engageable with the first groove at the first position of the first member and is engageable with the second groove at the second position of the first member.